Indiana Code Title 27. Insurance § 27-7-5-4

Sec. 4. (a) For the purpose of this chapter, the term uninsured motor vehicle, subject to the terms and conditions of such coverage, means a motor vehicle without liability insurance or a motor vehicle not otherwise in compliance with the financial responsibility requirements of IC 9-25 or any similar requirements applicable under the law of another state, and includes an insured motor vehicle where the liability insurer of the vehicle is unable to make payment with respect to the legal liability of its insured within the limits specified in IC 9-25-4-5 because of insolvency.

(b) For the purpose of this chapter, the term underinsured motor vehicle, subject to the terms and conditions of such coverage, includes an insured motor vehicle where the limits of coverage available for payment to the insured under all bodily injury liability policies covering persons liable to the insured are less than the limits for the insured's underinsured motorist coverage at the time of the accident, but does not include an uninsured motor vehicle as defined in subsection (a).

(c) An insurer's insolvency protection applies only to accidents occurring during a policy period in which its insured's uninsured motorist coverage is in effect and where the liability insurer of the tortfeasor becomes insolvent within two (2) years after such an accident.  However, nothing contained in this section shall be construed to prevent any insurer from affording insolvency protection under terms and conditions more favorable to its insured than is provided under this section.